1. Field of the Invention
This invention relates generally to vapor release dispensing devices and, more specifically, to a Two-part, Wall-mountable Electrochemical Dispenser.
2. Description of Related Art
In recent years, numerous devices and systems have been developed to treat the environmental air scent in public, institutional areas. The alteration of the environmental air in restrooms, hospitals, hotel lobbies, etc. has been achieved predominantly through the use of low-emission-rate fragrance dispensers. In order to serve the institutional market, these fragrance dispensers must not only provide low rate, long term fragrance emission, but must do so economically.
Dr. Henri Maget, alone and in cooperation with other inventors, has developed various such fluid releasers, as described in previous U.S. Pat. No. 4,902,278 (Maget I), U.S. Pat. No. 5,928,194 (Maget II), U.S. Pat. No. 6,383,165 (Maget IV), and U.S. Pat. No. 7,681,809 (Maget V). These patents disclose devices that release fragrances, pheromones or other such chemicals and mixtures at low rates (generally less than 1 mL of fluid per day). Other inventors have also developed dispensers as described in U.S. Pat. No. 5,899,381 (Gordon, et al), U.S. Pat. No. 6,451,808 (Cowles); and U.S. Pat. No. 5,785,688 (Joshi, et al), for example.
Often these active dispensers made use of a gas source to control the release rates of the dispensed fluid (and therefore also the emanation rates). Miniature gas sources, based on electrochemical reactions, have been described by Maget V. In general, for cost reasons, the electronic control of the gas generators in these active dispensers is accomplished by means of a simple, low-cost resistor. Also, in most instances, the electrochemical gas source is integrated into the dispenser. Problems have arisen whenever more complex delivery modes (e.g. variable fluid flow rates) or control functions (e.g. timers, end-of-delivery detection, etc.) are needed. The increased cost resulting from the cost of the electronics components, batteries, and the gas generator are not compatible with a single use dispenser. Consequently, it becomes desirable to split the delivery system into two subsystems—one permanent (or semi-permanent), and one disposable/consumable. The (semi)permanent subsystem preferably includes the gas generator and its related electronics, while the disposable subsystem generally consists of the fluid refill.
Two-part dispensers offer the advantage of multiple uses, so that the cost of the dispenser can be amortized over all of the uses (rather than a single use). These two-part dispensers couple economical refills that are replaceable once per month or so, with a (semi)permanent dispenser, replaceable once every 2-3 years or so. Such a dispenser is described by Maget, et al in U.S. Pat. No. 5,938,640 (Maget III). The battery-operated gas generation sub-assembly of Maget III is detachable from the fluid reservoir. Fluid delivery is achieved by the application of gas pressure to a membrane within the fluid chamber. The fluid reservoir is disposable, while the gas generation sub-assembly is re-usable.